试了下好像办不到呀

[postgres@jiekexu-test pgdata]$ psql “-pset fieldsep ‘\n’”
psql: error: invalid integer value “set fieldsep ‘\n’” for connection option “port”
[postgres@jiekexu-test pgdata]$ psql
psql (13.4)
Type “help” for help.

postgres=# \pset fieldsep ‘\n’
Field separator is "
".